Combined typewriting and computing machine



A. G. KUPETZa COMBINED TYPEWRIHNG AND COMPUTING MACHINE.

APPLICATION FILED MN. 25, 1917.-

1,356,072. Patented Oct. 19, 1920.

6SHEETSSHEET 1.

W/Messes: Q //We for: M w Z W Af/oxwe A. G. KUPETZ.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

APPLICATION FILED JAN. 25. 1917.

1,356,072. Patented Oct. 19, 1920.

6 SHEE1SSHEEI' 2.

@Hl Q M A. G. KUPETZ.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

APPLICAHON FILED IAN. 25, 191?.

A. G. KUPETZ.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

APPLICATION FILED lAN. 25. I917.

MNN

Q s g A. G. KUPETZ.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

APPLICATION FILED JAN.25, 1917.

1,356,072. Patented Oct. 19, 1920.

6 SHEETSSHEET 6.

/ 7 INVENTOR- M fl . wax

UNITED STATES PATENT OFFICE.

ADOLPH G. KUPETZ, OF NEW YORK, N. Y., ASSIGNOB TO UNDEBWOOD COMPUTDIG MACHINE COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

COMBINED TYTEWBITING AND COMPUTER IACHIN'E.

Specification of Letters Patent.

Patented Oct. 19, 1920.

Application filed January 25, 1917. Serial no. 144,323.

To all whom it may concern:

Be it known that I, Anonrrr G. Kurr'rz, a citizen of the United States, residing in New York city, in the county of Bronx and State of New York, have invented certain new and useful Improvements in Combined Typewriting and Computing Machines, of which the following is a specification.

My invention relates to combined typewriting and computing machines and is herein shown as applied to machines of the Underwood-Hanson type such as disclosed in applications of Hans I'Ianson, Serial No. (526,550, filed May 11, 1911; (now Patent No. 1,278,812 granted September 10, 1918) and Ogden hfinton, Serial No. 797,714, filed October 28, 1913 (now Patent No. 1,280,065, granted September 24, 1918).

In machines of this type the number to be computed is usually first set up one digit at a time in a nest of index pins, and the digits are later transferred simultaneously additively or subtractively into a totalizer.

It will be noted that in the hereinmentioned applications the type of computation is determined by the position of the typewriter carriage along the writing line and that the computing mechanism is so constructed as to perform subtraction by a method commonly known in the art as the complemental method of subtraction.

It will also be noted that the computing mechanism is so connected to the typewriter that the numbers computed will normally be written in red when subtraction is performed, and will be written in black when addition is being performed.

My invention is especially adapted to be used in connection with the keeping of commercial accounts, such as statement and ledger postings in which numbers are written in the various columns on the worksheets, and additively and subtractively computed on the machine.

In the keeping of commercial accounts it has heretofore been customary to write all numbers added on the computing machine in black, and all numbers subtracted on the computing machine in red, with the result that when writing numbers in the balance columns of the work-sheets, said numbers were written in black or red, depending upon whether addition or subtraction was being performed and regardless of whether the number representing the balance was a debit balance or a credit balance.

It has also been customary when beginnlng and completing a computation, to print a character, usually a star, adjacent the number representing the balance to indicate that the totalizer of the machine registers zero, viz: that the machine has been cleared, said star heretofore being usually written in the same color as the number adjacent thereto.

In my invention as herein disclosed, I have found it advantageous to provide mechanism which will enable the operative to write debit balances in black and print a black staradjacent thereto, and to write credit balances in red and also print a black star adjacent thereto, regardless of whether said balance is additively or subtractively computed. It will be noted that this mechanism as herein disclosed also enables the operative to print a red star optionally.

This mechanism may include a lug mounted on the typewriter carriage which is adapted, when the typewriter carriage enters a balance column, to operate the 'subtraction mechanism and to disconnect the bichrome mechanism therefrom, with the result that debit balances may be written in black, and subtractively computed, so as to clear the totalizer. When, however, it is desired to write a credit balance on the worksheet which is to be additively computed and written in red, there may be operated a credit-balance key, which when actuated will cause the mechanism to be reset to addition even though the said lug mounted on the typewriter carriage has set the machine to subtraction previous to the actuation of said credit-balance key, and the key will set the bichrome mechanism so that the number computed on the machine will be written in red and additively computed on the totalizer to clear the latter.

After said credit-balance has been run into the totalizer, the credit-balance key may be automatically released and the bichrome mechanism of the typewriter automatically reset so that a star may be printed in black, adjacent to said credit-balance, there being mechanism provided for the purpose.

ant 65, the lower end of which is adapted to engage and depress an arm 66, of which there is one for each pendant 65. Each of said arms 66 is mounted at the forward end of a rock shaft 67 journaled in a framework 68. Each rock shaft 67 has fast thereon one or more upstanding forked arms 69, adapted to engage a linkage 70, the lower reach 71 of which is adapted to engage and depress an index pin 72 at the depression of a numeral key when the typewriter carriage is in a computing zone. This depression moves the lower end of said index pin into the path of a cross bar 73 of a general operator 74, so that the number may be registered on a totalizer in a manner to be hereinafter described.

It will be noted by reference to Fig. 1 that the index pins 72 are normally out of the downward path of the linkages 71. In order that the index pins or digit members 72 mounted on the rack bars or denomination elements 75 may be moved into engaging relation with the linkages 70, 71, there are adjustably mounted on transverse bars 76, 77, fast to the typewriter carriage 28, denominational selecting dogs 78, one for each column on the work-sheet in which computation is to be performed. The dogs 78 are provided with pivotally mounted tappets 79 adapted to engage se'rz'atz'm, denominational jacks 80 when the typewriter carriage moves through a computing zone, said tappets and jacks being so formed that, as the carriage moves in letter feeding direction in a computing zone, said tappets will engage and swing said jacks in clockwise direction, as seen in Fig. l, to depress downwardly extending links 81. The lower ends of these are connected to transposition levers 82 so that the depression of each jack 80 actuates its transposition linkage 83 connected by a bell crank 84 to its pin bearing denominational bar 75 to move said bar forwardly and therewith its index pins 72, bringing the latter into alinement with said indexlinkages 70, 71. The transposition linkages 83 are so connected that each moves forwardly the pin bearing bar 75 corresponding denominationally to the jack 80, which is actuated by the tappet 79, so that the only pin which will be depressed will be that corresponding to the numeral key actuated on the denominational bar moved forward at the moment. It will be noted in passing that each denominational bar 75 is provided with a number of pins, one less than its exchange value to next higherdenomination.

In order that the number thus indexed may be registered on the' totalizer of the machine, there are provided computing or dial wheels 90 (Fig. 1) connected by the usual Hanson one-way pawl and ratchet clutch (not shown herein) to a pinion 91,

constantly meshing with a rack 92, formed on the forward end of the pin bearing bar 75. This rotates its dial wheel 90 in clockwise direction, as seen in Fig. 1, when the general operator cross bar 73 is moved forwardly to engage the depressed pin bars 72 and thereby drive the connected rack bars forwardly.

To start a cycle of operations in which the general operator 74 may be automatically thus reciprocated to run into the dial wheels of the machine the number indexed on the pins 72 at the completion of the indexing of said number, there is provided fast to the frame-work of the machine (Figs. 1 and 3) a lever or trip 97, pivoted at 98, having a tappet 99 thereon adapted to actuate said trip when a portion 100, formed on the dog 41, strikes a cam surface of said tappet 99 depressing the latter and actuating the connected lever 97. This takes place during the letter-space motion of the carriage 28 subsequent to the writing of a digit in units of cents denomination. The actuation of the lever 97 draws a link 101, connected to one end thereof, upwardly, to rock a bell crank 102, connected to a slide or latch 103, moving the free end of said latch out of the path of a lever 104 fulcrumed at 105. This causes the forward end thereof to depress a pin 106 and therewith a vertical slide 107 and urged to rotate in a counter clockwise direction by a spring 104. The lower end of this shde straddles one end of a lever 108, pivoted midway its ends, and the slide raises the other end 109 thereof, and therewith a latch 110, of a motor trip mechanism to release a spring pressed clutch member 111 forming a part thereof, so that a motor controlled thereby (not shown herein) may be effective. This reciprocates the general operator connected thereto in a manner as illustrated and described in patent to John N. Thornton, No. 1,146,371, dated July 13, 1915, thus rotating the dial wheels amounts directly proportional to the value of the depressed pins 72. To reset the spring pressed lever 104 and connected parts to'normal position, there is provided at the forward end of said lever an extension 112 (Fig. 3) adapted to be engaged by a cam 113, formed on the general operator 74, to swing said lever to its normal position at the forward stroke of the general operator. The associated parts may be returned to normal position by a spring 102 (Fig. 1).

The motor for actuating the general operator may also be started manually, there being provided for the purpose a key 120, mounted on a key bar 121, which may be manually depressed against the tension of a spring 122. This swings downwardly an arm 123 connected thereto and overlying the motor trip lever 108, to actuate the latter in the same manner as at the depression of the vertical slide 107 hereinbefore described, and in a similar manner as illustrated and described in said Patent, No. 1,110,371.

In addition to the present machine being capable of performing addition, it is also capable of performing another type of computation, namely, subtraction. For thls purpose, the pin-setting mechanism including the shafts (37, the linkages 70, 71, and the arms 66. is of shiftable type, as explained in said Hanson application, No. 626,550, so that it may be changed to set pins corresponding to the complements of the digits represented by the numeral keys struck instead of the direct values. That is to say, the mechanism is arranged to carry on what is called complementary subtraction, which consists in rotating all of the computing wheels amounts corresponding to the complements of the values of the keys actuated for the particular computing wheels. To do this, the shafts 67 are shifted in the manner described in said Hanson application above referred to, to bring the arms 69 out of engagement with pins on one side of the upper reaches of the linkages 70, and into engagement with opposite pins on the juxtaposed upper reaches of these linkages.

The shafts 67 are shiftable thus in unison by a universal bar 127, which engages a series of alined notches provided in the shafts 67. The universal bar 127 is pivoted at its upper edge and is provided with an arm 128 which is engaged with and actuated by an arm 129 on a rock shaft 130. The rock shaft 130 is provided with a second arm 131, which is bifurcated to engage a pin 132 provided on a subtraction or controlling bar 133. The subtraction bar 133 is normally locked in a forward position against the tension of a spring 134 by a latch or detent 135, which engages a notch 136 provided in the subtraction bar 133.

In order to release the detent 135 and thus permit the spring 134 to] retract and draw the subtraction bar 133 with it, the detent 135 is secured to a shaft 137, which is also provided with an arm 138, whereby this shaft may be rocked against the tension of a spring 139, Fig. 3. The rocking of this shaft 137 may be done manually by means of a subtraction key 140, which projects outwardly from the front part of the casing 141, and has a subtraction rod 142 extending rearwardly to pivotal engagement with the arm 138. It will readily be seen that when the subtraction key 140 is pressed rearwardly, the shaft 137 will be rocked, removing the detent 135 from engagement with the notch 136 so as to permit the spring 134 to retract the subtraction bar 133, thus rocking the bell crank comprising the arms 131 and 129, whereby the uni versal bar 127 will be rocked forwardly to shift the shafts 67 and the arms 69 carried thereby, from their adding to their subtracting position.

In addition to re-arranging the pin-setting mecha-nism to set complementary numbers, it is also necessary to set the 9 pins, as explained in the said llanson application No. 626,550. For this purpose each of the 9 pins is provided with a reduced neck engaged by a shift lever 1433, Figs. 1 and 11, which is pivoted in each case on its own denominational bar or member 75. These shift levers 143 underlie a universal bail 144. The bail 144 is held in its uppermost position clear of the levers 143 by a spring 150 coiled about a rock shaft 145 on which the bail is secured.

When the subtraction bar 133, however, snaps rearwardly under the traction of the spring 134, a hook 146 pivotally mounted on the bar 133 and engaging in a notch 147 provided on an arm 148, also secured to the rock shaft 145, will rock the latter and the bail 144 so that the latter will come down and depress the forward ends of the lovers 143 and thus set the 9 pins. Before the subtraction bar 133 has entirely completed its rearward motion, an arm on the hook 146 will come into engagement with a stop or disconnector 149, whereby this hook will be rocked against the tension of a spring 151 out of engagement with the notch 147 permitting the spring 150 to act to retrieve the bail 144 and thus leaving the 9 pins and their levers 143 free and clear in their set position.

In addition to setting for subtraction manually, means is provided whereby the mechanism may be adjusted for a subtraction computation automatically at a predetermined point in the travel of the carriage 28. For this purpose there is provided on the rack 43 carried by the carriage 28, a subtraction dog 152 (Fig. 10), which has a portion 100 adapted to actuate the motor trip or tappet 99 at the end of a subtraction zone and which is also provided with an ex tension 153, extending for substantially a computing zone, which extension projects to such an extent that it will engage a trip 154 and rock the same when a subtraction zone is reached. The trip 154 is connected to pull on 'a link 155 so as to rock a bail bell crank 156, which is connected to withdraw a latch 157 from beneath one arm of a bell crank 158 loosely mounted on the shaft 137.

The bell crank 158 is provided with a second arm 159, to which are secured a pair of springs 160 and 161, which tend to rock the bell crank 158, which is normally prevented by the latch 157. When this latch 157, however, is withdrawn in the manner described, the bell crank 158 will be rocked -so that the arm 159 carried thereby will engage a lug 162 on an arm 163 secured to the shaft 137. The shaft 137 will thus be rocked to withdraw the detent 135 from engagement with the notch 136, permitting the subtraction bar 133 to be snapped rearwardly to its subtraction-setting position by the spring 134.

The return of the bell-crank 158 to its normal position is effected during the forward movement of the general operator, the bar 73 of which engages the cam 158 and rocks said bell-crank in a counterclockwise direction as represented in Fig. 3, so that the latch 157 and the coiiperative parts may be returned to their normal positions by the spring 156 (Fig. 1).

The running up of a subtraction computation into the computing wheels 90, automatically retensions the spring 134 and resets the subtraction bar set to a normal passive position corresponding to an adding action. This is done by the cross bar 73 which engages a lug 164 provided on the subtraction bar 133 and thereby carries said bar forward. The spring-134 and the bar 133 will be held in a passive position by the latch 135 engaging in the notch 136 automatically.

If it is desired to throw the computing mechanism out of operation, a non-add key 165 may be pressed inwardly so as to operatively disconnect the computing mechanism from the type-writing mechanism.

Before going into details of this mechanism, it would be well to mention the fact that the tappets 78, 79, are not normally in a position to actuate the jacks 80. That is to say, these tappets 78, 79, are each pivoted on the bar 76 and rest in a depressed position on the bar 77, so that if they travel in this position beneath the jacks 80, they clear them without operating them. However, when a tappet 78, 79, comes into a computing zone, a zone-controlling or silencing roller 166 cams the tappet 78 upwardly by engagement with a follower roller 167 on the tappet, and thus raises the tappet to such a height that it will engage and operate the acks 80 in succession. The zonecontrolling roller 166 is mounted on a pair of arms 168 secured to a rock shaft 169 and is normally held in a position to engage the follower roller 167 by means of a spring 170. The zone-controlling roller and the mounting therefor, however, can be moved against the tension of the spring 170 to swing the zone-controlling roller 166 out of the path of travel of the follower roller 167, so that if a tappet comes along at such a time with the zone-controlling roller at its ineffective position, the tappet passes idly beneath the jacks 80 without being raised to action.

Now, then, if the non-add key is p inwardly, it forces its stem 171 before it, which stem is pivotally connected at 172 to a thrust rod 173, so that the latter is actuated to rock a bell crank 174 to which it is pivoted. The bell crank 174 is provided with an arm 175 having a pin 176 underlying an arm 177 on the rock shaft 169. It will thus be seen that when the non-add key 165 is pressed inwardly, it moves the zonecontrolling roller 166 against the tension of the spring 170 to its ineffective position, thereby silencing the denominational members 75, because the typewriter carriage 28 is ineffective on them. Under these circumstances the numeral keys 21 actuate the pinsetting mechanism idly as the lower reaches 71 of the linkages pass idly between the rows of pins 72.

Connection is made whereby the non-add key 165 not only silences the denominational control, but also silences the automatic motor-trip-controlling mechanism and the automatic subtraction setting mechanism whereby, although the carriage in its travel may actuate tappets or trips 99 and 154,- the general operator, in the first instance, will not be automatically actuated, and the subtraction-setting mechanism, in the second instance, will not be automatically brought into pla To do this the thrust link 173 is provid with a pin 178, which engages a lever 179 pivoted intermediate its ends on a shaft 180 and carrying at its lower end a pin 181 which extends through a slot 182 provided in a latch arm 183 pivotally mounted on the shaft 180. 7

Thus, when the non-add key 165 is pressed inwardly, it causes the thrust link 173 to rock the lever 179 against the tension of the spring 160, which is connected thereto. This moves the pin 181 in the slot 182, permitting the spring 161, which is connected to the latch arm 183, to draw the latch arm 183 forwardly from the Fig. 3'position so that a hook latch 184 will catch and hold a stud 185 provided on the bell crank arm 158, thereby holding said arm against its normal operation, in which it releases the latch 135 on an actuation of the subtraction trip 154. The latch 184 is also provided with a toe 186 which engages over a stop 187 provided on the lever 104 to lock that lever against actuation.

It will thus be seen that while the nonadd key is in its effective position, the bell crank 158, 159, will be prevented from rocking under the impulse of the springs 160 and 161, and also the lever 104 will be prevented from rocking under the impulse of its spring. Under. these circumstances, even if the latches 103 and 157 are withdrawn, the subtraction-setting mechanism and the clutch-closing mechanism will not be operated, so that the automatic means for controlling the setting for subtraction and the driving of the general operator by the motor, are silenced.

lit will be noted in passing that the spring 160 is considerably stronger than the spring 161, so that when the non-add key 165 is returned to its inactive position the spring 160 will return the lever 179 and the latch arm 183 to their ineffective positions.

The non-add key 165 when once actuated or pressed in to disconnect the computing mechanism from the typewriting mechanism, is locked in its actuated position so as to enable the operative to use both hands in operating the machine. For this purpose there is rovided on the-thrust link 173 a pin 188 Figs. 1 and 3), which engages in an L-slot 189 in a stationary portion of the frame of the machine. The reach of this EL-slot extends horizontally to guide the link 173 while being pressed rearwardly and joins with the bend or off-set of the lL-slot at a point where the pin 188 reaches the end of its movement so that a spring 195 will cause the pin 188 to drop into the oft set, preventing the return of the link 173 and the non-add key 165. To return the nonadd key 165 and the link 173 and the parts con nected thereto to thei rinactive positions, it is sufficient to actuate the general operator either manuall or from the motor although the key may a so be returned by depressing the finger-piece 165 thereof, so that it fulcrums on the frame and lifts the pin 188.

The automatic releasing mechanism for the non-add key 165 includes a cam 190 secured on the usual shaft 191 provided for manually actuating the general operator so as to rotate therewith. This cam has a depressed portion thereof normally in register with a. releasing rod 192 when the general operator 74 is in its home position. WVhen, however, the general operator is moved forward, the shaft 191 will be rotated through the usual pinions 193 and segments 194, so as to bring the rise of the cam into engagement with the releasing rod 192, raising the same against the tension of the spring 195 which is connected thereto. This releasing rod 192 is also connected to the thrust link 173, so that it will raise the latter to bring the pin 188 out of the offshoot of the l..-slot 189, permitting the springs 170 and 160 to return the non-add key 165 to its inactive position. The releasing rod 192 is guided in its movement by having pinand-slot connections 196, 197 (Figs. 1, 3 and 7) with a bracket 198 loosely mounted on the shaft 191.

Each of the computing wheels 90 (Fig. 1) is normally held alined so as to display its numerals through a sight-opening 200 by a detent 201 pivoted below the wheels 90 on a shaft 202, and normally held engaged with shallow teeth 203 on the computing wheels by a spring 204, in a manner illustrated and described in Patent No. 1,256,309, granted February 12, 1918, to Richard F. Hoyt.

Before beginning to write a number which is to be registered on the computing wheels 90 (Fig. 1), it is desirable to print a sign showing that said wheels stand at zero when the computation is begun. To so print a sign, the machine is provided with a starprinting key 205, and said key is provided with such connections that if it is operated when the computing wheels stand at zero, it will cause a special type to print a star on the work-sheet on the platen, but at other times said star cannot be printed.

To bring this result about, there is provided a special type-bar 206 provided with a type-head 207 comprising the type (Fig. 1), and the usual heel 29, which typebar whenever the star key 205 is operated, automatically rises to print against the platen 27. To cause such automatic printing, the type-bar 206 has a key lever 208 of the usual kind, which however is cut off at 209 and, by connections described hereinafter, is normally under tension of a spring 210 which tends to swing the typebar 206 upwardly to print. Said spring, however, is normally prevented from operating by a holding catch 211.

The connections between the spring 210 and the key lever 208, include a link 212 (Fig. 1), extending downwardly from said key lever to a rock arm 213 fast on a rock shaft 214, said rock shaft also carrying a rock arm 215 directly behind 213 and the spring 210 being connectedthereto. Thus, said spring 210 tends to swing the rock shaft 214 to operate the type-bar 206, but the rock arm 215 is normally supported by a pendant link 216 pivoted on said rock arm and carrying at its lower end a lug 217 which normally rests on the catch 211 and is held up thereby.

Said catch 211 is swung to ineffective position Whenever the star key 205 is operated, thereby causing the spring 210 to operate the type-bar 206. To thus swing the catch 211, the star key 205 has its stem extended downwardly to rest on a rock arm 218 fast on a transverse shaft 219 on the machine, and said shaft also has fast thereon the catch 211 so that rocking of the shaft 219 by the star key 205 will swing the catch 211 clear of the lug-217 and permit an operation of the star type-bar 206.

\Vhen the star type-bar has thus been operated, the type-bar is returned to normal position and the spring 210 retensioned by the operation of the general operator. For this purpose the usual carry-over drive shaft 220 of the carry-over mechanism is employed. said shaft provided with a pinion 221 and the one-way clutch for driving it in one direction only, i. e., during the re turn stroke of the general operator in a manner similar to that described and illustrated in said Hanson application. Said drive shaft 220 is provided with a cam 222, which ,cam during said return stroke carries its high end under a lug or roller 223 fast on the rock arm 215, and lifts said rock arm against the tension of the spring .110, thus restoring the star type-bar 206 to normal position and drawing the link 216 up past the catch 211, so that said catch will be again effective to hold the lug 217. The lower side of the catch 211 is formed as a cam to swing the link 216 clear of it in its upward stroke.

To permit the link 216 to thus swing past the catch 211, said link is pivoted on the rock arm 215, and its lower end is normally swung forwardly to effective position by a spring 224. The lower end of said link 216 is extended so that said link will strike the shaft 219 and be prevented from swinging too far forwardly under the tension of the spring 224. The catch 211 is normally swung rearwardly under the lug 217 by a spring (not shown herein), which encircles the shaft 216 and holds the catch to its normal effective position.

If the computing wheels do not stand at zero, it is impossible to operate the star key 205, because unless said wheels stand at zero, one of the detents 201 will be swung outwardly, as seen in Fig. 1, to carry a bail 225, also pivoted on the shaft 202 under a lug 226 fast on the star key stem to lock the star key against operation. In order that the star key may be depressed the computing wheels 90 are provided with specially cut-away teeth 203 at such a point in their revolution that the detents 201 will sink between said cut-away teeth deeply enough to allow the bail 225 to be swung forwardly by its spring 204. At the other points the teeth 203 will hold the detents 201 far enough out to swing the bail 225 under the lug 226 of the star key stem.

Since the cut-away teeth 203 are so placed that they permit the detents 201 to enter them when the computing wheels stand at zero, the bail 225 will stand clear of the star key lug 226 when the computing wheels are at zero, and thus said star key 205 can operate the star-printing mechanism when the computing wheels are at zero.

The herein-described star key actuating mechanism may also be used to print a star on the work-sheet at the end of a computation as will hereinafter appear. The abovedescribed star-printing mechanism is fully illustrated and described in the above-mentioned Hoyt Patent, No. 1,256,309.

The various parts of the mechanism thus far described are substantially identical with those in the herein mentioned appli cations and patents, and I have found it advantageous to illustrate my invention as applied thereto. v

As hereinbefore stated the machine is adapted to perform computations in connection with the keeping of commercial accounts, an example of which is shown in Fig. 9, in the form of a ledger sheet. It will be noted by reference to Fig. 9 that the ledger sheet herein illustrated is divided into four computing columns correspond-, ing to four computing zones on the machine, the denominational selecting dogs 78 and the decimal tabulating stops 41 (Fig. 10) being placed along the carriage 28 at corresponding letter-space positions. The first computing column on said ledger sheet is headed Debits and all numbers posted therein are advantageously added in the computing machine and written in black. The second column is headed Credits, and all numbers posted therein are advantageously subtracted in the computing machine and written in red. The third column is headedBalance andnumbers posted therein are either subtracted and written in black or added and written in red, depending upon whether the balance posted is a debit balance, or a credit balance, respectively. The fourth computing column is headed Old balance, and numbers posted therein are added and written in black, or subtracted and written in red, depending upon whether the balance is a debit balance, or a credit balance, respectively. It will also be noted by reference to Fig. 9, that the ledger sheet is provided with columns wherein a character. preferably a star, may be printed to indicate that the totalizer of the computing machine is at zero, at the beginning, and at the end of a computation, said columns being advantageously placed adjacent their respective balance columns.

In order that postings may be made and computed on the machine, the ledger sheet shownin Fig. 9 is placed on the platen in such position that the computing columns thereon will be in letter-space positions corresponding to the denominational selecting dogs 78, and the number first written, is the one in the old balance column representing the old balance on the account of the customer. For this purpose there is provided on the rack 43 a decimal-tabulator stop 233 placed on the rack in a position corresponding to that of the old balance column, and there is correspondingly located an associated dog or denominational selector 78. The stop 41 is formed so that when the carriage enters the old balance computing zone the debit balance written in said column will be additively indexed on the computing machine. The balance is subsequently added in the totalizer by the reciprocation of the general operator the decimal tabulator dog 233 being provided with a portion 100 adapted to actuate the motor trip 97 during the letter-space movement of the typewriter carriage subsequent to the writing in units of cents position in said old balance column.

The next posting on said ledger sheet as illustrated in Fig. 9 is a number in the debits column, which is additively indexed on the machine and registered in the totalizer, there being provided a denomination selector and a decimal tabulator stop 234, similar in form to the decimal tabulator stop 233, and also mounted on the rack 43 in a letter space position corresponding to that of the debits column, on the ledger sheet. If, however, the next posting should be a credit, the latter will be written in the credits column, and subtractively indexed on the computing machine and written in red. For this purpose there is provided on the rack bar 43, a decimal tabulator stop 235, carrying the extension 153, to actuate the state-setting mechanism by the trip 154 when said credits column is reached and thereby set the machine to subtraction. In order that the number in the credit column may be written in red, the

\ bichrome mechanism is connected to the subtraction setting mechanism in such a manner, as to be actuated to write red at the depression of any numeral key 21 after said subtraction mechanism has been shifted from its normal (Fig. 1) position to its actuated or subtraction position shown in Fig. 4. For this purpose, there is fast on the rock shaft 130 of the subtraction setting mechanism, a rearwardly extending arm 2336 (Figs. 1 and 4) the rear end of which has pivoted thereto an upwardly ex tending thrust link 237, the upper end of which slides in a slot 238 (Fig. 3) and normally underlies an interponent 239 connected to the ribbon selecting mechanism. When the subtraction bar 133 is retracted to set the computing mechanism to subtraction the thrust link 237 is moved upwardly and moves the interponent 239 therewith from the Fig. 1 position to the Fig. 4 position to set the bichrome mechanism to write red. For this purpose, the interponent 239 is guided at its lower end between two pins 240, Figs. 1 and 3, and pivoted at its upper end to an arm 241 fast to the rear end of the bichrome shaft 50 to rock said shaft against the tension of a spring 242. This swings the arm 51 and the connected link 52 toward the right of the machine to engage one of the slots 54 formed in the slide 53, Fig. 1, with the pin 55 fast on the ribbon-vibrating lever 57, thereby setting the ribbon-vibrating mechanism, so that when the ribbon 59 is actuated, the red field thereof will be moved into the nth of the types at the depression of any zey 21, 22. his causes all numbers which are subtracted in the comweeps/2 puting machine and posted in the credits column to be written in red. If the credit posting is a lesser amount than the old balance, which is a debit posting, the resulting new balance will still be a debit balance and will be the difference between the two amounts and advantageously written in black. If, however, on the other hand, a debit posting was written on the ledger sheet directly subsequent to the entry of the old balance, the posting will be also a debit balance and will amount to the sum of the two postings. At the end of this computation, the totalizer will exhibit at the sight opening 200, the total of said postings which is the new balance. This also is a debit balance and is therefore advantageously written in black on the work-sheet, but is advantageously subtracted in the totalizer of the machine, since it is desirable to clear the totalizer at the end of said transaction and to print a star adjacent said balance to prove the accuracy of the computation.

To accomplish this result there is provided on the rack 43 the decimal tabulator dog 152 placed in a letter space position corresponding to the balance column, and provided with an extension 153 adapted to actuate a subtraction trip 154 when the balance column is moved into the computing zone. l/Vhen said balance column becomes a computing zone, the machine will therefore be set for subtraction by said trip and unless the connections are altered will cause the thrust link 237 to move upwardly to set the ribbon mechanism to write red. It is, usually, however, advantageous to write said debit balance in black. To do this, mechanism is provided whereby the connection between the subtraction mechanism and the ribbon setting mechanism is broken when the balance column on the ledger sheet is moved into the computing zone.

For this purpose the decimal tabulator dog 152 is provided with an extension 246 (Figs. 1 and 3), so placed relative to the extension 153 that when the balance column enters the computing zone, said extension will be moved into engagement with a trip 247 fulcrumed at 98 to raise from normal position the link 248 connected to one end thereof. The lower end of said link (which is held in normal position by returning spring 248) is connected to a rearwardly extending arm 249, fast to a rock shaft 250, on which is rigidly fast an upstanding arm 251. llhis last is connected by a link 252 to the interponent 239, so as to move said interponent forwardly at the actuation of the trip 247, thus swinging the lower end of said interponent out of the path of the thrust-link 237. That, is, the interponent is swung from the Figs. 1 and 3 position to the Fig. 5 position, in which latter the actualion of said thrust-link 237 and connected subtracting mechanism is idle. Since it is idle. it is inefi'ective to actuate the ribbon selecting mechanism, which, therefore, remains under the influence of its spring 242 set to write black. It will be seen from the foregoing that by means of the herein-described mechanism, numbers written in the balance column will be written in black and subtracted on the t0- talizer, thereby causing the dial wheels thereof to exhibit zero at the sight opening 200, thus permitting the usual star to be printed adjacent to the balance at the right thereof.

If, however, a credit posting is a larger amount than the old balance, the dial wheels 90 of the totalizer will be rotated subtractivcly and a greater amount will be subtracted thereon than that previously exhibited at the sight opening, thus causing an overdraft and indicating a credit bal ance.

The operative will notice that a credit balance is indicated on the totalizer by the fact that all those dial wheels of high denomination exhibit 9, on which no computation was performed, due to the fact that the machine herein described performs subtraction by the complemental method as described in said Hanson application. When a credit balance is thus indicated on the totalizer, the amount representing said balance may be written in the balance column and is advantageously written in red and added on the computing machine so as to return the totalizer to zero. This is ac complished by writing the complements of the digits represented on the dial wheels of the totalizer which correspond to the credit balance.

It will be seen from the foregoing that the decimal tabulator stop 152 corresponding tothe balance column is adapted to set the machine to subtraction. This, however, is often disadvantageous since it is desired to add in the balance column when a credit balance is written therein as described just above.

To overcome this, there is provided mechanism whereby the computing machine may be retained in its adding state and the ribbon selecting mechanism will be set to write red even though the decimal tabulator stop 152 for that zone is equipped to set the machine to subtraction, and even though the machine is equipped to normally write black when addition is being performed; This mechanism includes a credit balance key 260 (Figs. 1, 3, 6and 7), slidably mounted in the casing 141 at the forward end of the machine and fast on a stem 261, the rear end of which is slidably mounted in a bracket at 262, and is advantageously placed parallel to and below the thrust rod 173 of the non-add key 165. When the credit balance is shown on the totalizer, the credit balance key 260 may be actuated either before or after the balance column comes into the computing zone, and before the credit balance is written.

In case said credit balance key is actuated before said balance column comes into the computing zone, it will prevent the actuation of the subtraction setting mechanism when the extension 153 actuates the subtraction setting trip 154. For this purpose, there is formed in the credit balance key stem 261 a notch 263 engaging the upper end of a vertically disposed lever 264, fulcrumed between its ends at 265 (Fig. 3). The lower end of this lever is provided with a pin 266 (Figs. 1, 3 and 7), which when the credit balance key is actuated swings forwardly into engagement with the bell crank arm 159 of the subtraction setting mechanism and holds said arm against actuation when the other arm of said bell crank 158 is released by the actuation of the latch 157. This holds the subtraction bar 133 in its normal adding position.

If, however, the balance column comes into the computing zone previous to the depression of the credit balance key 260 the extension 153 corresponding thereto will actuate the trip 154 to set the machine to subtraction and the ribbon mechanism to write red. Then the credit balance key may be actuated to swing the lever 264 so that the pin 266 thereon will engage the arm 159, and return the lever to its normal position against the tension of the springs 160, 161. In order that the actuation of the credit balance key 260 may also cause the subtraction bar 133 and connected mechanism to be reset to normal adding position, the stem of said key is provided with a notch 267, formed near its forward end (Figs. 3 and 7), which engages a bell crank 268, fulcrumed at 269 to swing the latter at the actuation of the credit balance key, so that one arm thereof, which overlies a pin 270, fast on the manual motor key bar 121 will depress said bar against the tension of the spring 122 to trip the motor driving mechanism. This reciprocates the general oper ator, the cross bar 73 which will engage the lug 164 of the subtraction bar 133 and return the latter to its normal position, at which time the detent 135 will snap into the notch 136 to hold said subtraction bar in its forward adding position. Although the general operator turns all the wheels by the 9 pins which were set for the subtraction operation, the complete stroke of the general operator completes the cycle of operations, automatically subtracting zero and returns every wheel to its previous reading.

In order that the general operator driving mechanism may be silenced at the end of the reciprocation of the general operator caused by the depression of the credit balance key, mechanism is provided whereby the latch 110 is restored to effective position, even though the manual motor trip key 120 and connected parts remain in depressed position. For this purpose, there is provided (Figs. 1, 3, 7 and 8) a slide or interponent 273 mounted on the arm 123 and adapted to slide lengthwise thereof against the tension of a spring 274, which tends to move and hold said slide in its rearmost position, so that an extension or lug 275 formed thereon normally overlies the right end of the motor trip lever 108. To release the lever 108, so that the latch 110 may be moved to effective position, there is formed on the general operator 74 an extension 276, which near the end of the forward stroke of the general operator engages an extension 277 formed on the slide 273 to move the latter forwardly against the tension of its spring 274 from the Fig. 6 position to the Fig. 7 position. This moves the extension 275 out of engagement with the lever 108 and permits the latch 110 to arrest the clutch member 111 of the general operator driving mechanism at the completion of the return stroke of said eneral operator. The writing of the credit balance will then cause it to be additively computed in the machine, thus returning the totalizer to zero. It will be understood that with the slide 273 the driving mechanism is prevented from moving through more than one cycle in case any one of the keys 120 and 260 is continuously held in its actuated position by the operative.

In order to cause said credit balance to be written in red there is formed in the credit balance key stem 261, a notch 278 (Figs. 1, 3, 6 and 7) in engagement with a bell crank 279 (Fig. 3) fulcrumed at 280 to the top of the casing 141 of the computing mechanism. At the depression of the credit balance key 260, the bell crank 279 is swung to move leftwardly, as seen in Fig. 3, thus drawing a slide 281 pivoted thereto, so that a cam 282 on said slide and normally out of engagement with the interponent 239 will engage and raise said interponent. This swings the rock shaft 50 and connected parts against the tension of the spring 242, set ting the bichrome mechanism to write red. in order that the credit balance key 260 may be held in its actuated position until the completion of the posting and computing on the credit balance, the credit balance key stem is provided with a projection 286 having a cam surface 287 formed thereon (Fig. 3), which at the depression of the credit balance key engages a cam surface 288 of a detent 289 formed on the thrust bar 173 of the non-add key, thereby raising said thrust bar and connected rod 192 against the tension of the spring 195, so that the projection or extension 286 may pass behind the detent 289. The latter is snapped downwardly by said spring 195 to hold the key stem 261 and connected parts in actuated position, the'slot 189 (Fig. 1) in which the pm 188 moves, being of suflicient width to permit the upward movement of the thrust bar 173.

To release the credit balance key 260 from its actuated position at the end of the computation, there is provided on the general operator shaft 191, the cam 190 (Fig. 3), which at the end of the forward stroke of the general operator raises the releasing rod 192 to raise therewith thrust rod 173 and the detent 289 thereon from in front of the extension 286, as seen in Fig. 8. This moves said detent out of the path of extension 286, permitting the credit balance key and connected parts to be moved forwardly under the influence of the spring 271. Simultaneously the interponent 239, which bears down on the cam surface 282 is moved to its lowermost position, thereby permitting the resetting o the machine by the spring 242, to write black while the computing mechanism is restored to its normal adding position. It will be noted that the cam 190 is actuated to release the credit balance key during the letter-space movement of the typewriter carriage subsequent to the writing of .units of cents in the balance column. At the same time the general operator is actuated, because portion 100 on the decimal tabulator step 235 actuates the motor trip lever 97 to raise the latch 110 and release the general operator driving mechanism.

If it is desired to reset the machine for normal operation when the credit balance key has been erroneously depressed, the manual motor starting key 120 may be actuated to reciprocate the general operator, even though the starting key was previously depressed by the actuation of the credit balance key 260, and is held thereby in a depressed position in the manner described above. To permit this second actuation of the starting key 120, the slide or interponent 273 has, thereon, a step or secondary lug 290, which is of such a height that when the slide 273 is freed from the lug 276 on the return stroke of the general operator, the said secondary lug 290 can slip over and overlie the lever 108, the end 109 of which engages the starting latch or pin 110 of the motor. To enable this to be accomplished, the projection 286 on the credit balance key is overthrown (in Fig. 6) beyond the detent 289 of the non-add key to a considerable extent in actuating the motor starting key 120, so that when the finger of the operative is removed from the credit balance key, said starting key returns through part of its stroke, and this part of its return stroke is suflicient to allow the secondary lug 290 to slip over on to the lever 108 (see Fig. 8). Therefore, a second depression of the starting key 120, with the parts set as in Fig. 8, will start the motor.

It will be seen that restoration of the credit balance key to normal position may be effected by means of the non-add key 165. Upon depression of the non-add key, with the various parts positioned as shown in Fig. 8, the stem 261 of the credit balance key will be forced to the rear due to the engagement of projection 286 and detent 289, and will effect, through bell-crank 268, a depression of the manual motor-starting key suflicient to start the motor, thereby causing a reciprocation of the general operator and consequent release of the credit balance key.

It will be noted that the depression of the credit balance key 260 causes a simultaneous depression of the motor starting key 120, which is followed by a reciprocation of the general operator and actuation of connected parts including the cam 190. In order that the actuation of said cam may not immediately release the credit balance key, the operative should retain said key 260 in its depressed position until the end of the return stroke of the general operator after which the operative may be free to use both hands.

It will be noted that after a credit balance is written in red in the balance column, the ribbon mechanism is reset to write black at the release of the credit balance key 260, after which the star key 205 (Fig. 1) may be actuated to print a black star adjacent the number representing said credit balance to indicate that the totalizer is at zero and the computation and ledger postings have beennccurately made. If, however, the operative desires to print black stars adjacent debit balances and red stars adjacent credit balances, this may be accomplished by depressing the credit balance key immediately before printing. It may also be accomplished by the depression of the key 49 (Figs. 1 and 3), but in the latter case said key must be held there manually against the tension of the spring 242 until the completion of the printing of said star.

When a credit balance is written in the old balance column at the beginning of a computation. it is advantageous to write the number representing said balance in red and to subtractively compute said number in the totalizer. The decimal tabulator stop 233 corresponding to said column is however, not provided with an extension 153 to set the computing mechanism to subtraction, since it is desirable at times to post debit balances in said column which are to be added on the totalizer. The operative may determine before beginning a computation that the posting in the old balance column is a credit balance by reference to the ledger sheet containing the customers last transaction, and, having thus ascertained the value of the old balance, set the machine to subtractively compute said balance and to write said balance in red. For this purpose, the machine is provided with a subtraction key 140, which when actuated from the Fig. 3 to the Fig. 4 position releases the subtraction bar 133 as hereinbefore described, thus setting the machine to subtraction, and the ribbon mechanism to write red.

At the end of this computation, the general operator driving mechanism automatically reciprocates the general operator, there being provided on the decimal tabulating dog 233 a portion 100 for the purpose. The number thus written is subtractively run into the totalizer, which will exhibit the true complement thereof, after which computation may be continued when writing on the debit or credit column on the work-sheet, and the resulting balance read on the dial wheels of the totalizer.

It will be noted in passing that the decimal tabulator stops 152, 233 and 234 (Fig. 6), are constructed in a manner similar to those illustrated and described in application of Frederick A. Hart, Serial No. 39,751, filed July 14, 1915, (now Patent No. 1,296,953, granted March 11, 1919).

If a credit posting has been erroneously made on the ledger sheet and subtractively computed on the machine, and it is desired to correct said error, it is advantageous in so doing to add the amount thus posted on the machine and in rewriting to superpose the number over the number erroneously written. It is also advantageous to superpose said number in the same color as the one erroneously written, thereby minimizing the amount of erasures required on the work-sheet. For this purpose, the credit balance key may be actuated in the hereinbefore described manner to set the computing mechanism to addition and the ribbon mechanism to write red, thereby correcting the error in the computing mechanism and avoiding the number being written on the work-sheet in a variety of superposed colors. This being done. the one or more digits of said number which were erroneously written may be erased from the work-sheet and the correct number superposed in its place and correctly computed in the machine.

It will be noted in connection with the herein-mentioned example of work (Fig. 9), that the credit balance key may be actuated for the purpose of error correction in either the credits column or the old balance column. wherein it is desirable when making corrections to add in the'computing mechanism simultaneously with the writing of the number in red.

Variations may be resorted to within the scope of the invention, and portions of the im rovements may be used without others.

Iaving thus described my invention, I claim:

1. In a computing machine, in combination, a variably settable computing mechanism, capable of effecting computations of different character, dependent upon its setting, means for printing numbers computed in any one of a plurality of different colors, said printing means including variably settable polychrome mechanism for selectively determining the printing color at each printing operation, said printing means also including a traveling carriage and means controlled thereby for determining a zonein which a number printed may be computed, means, including parts normally operated on movement of said carriage into said zone, for effecting an automatic setting, by varying the relations of parts of said mechanisms, so as to prepare said machine to effect a computation of a predetermined character and to print in a predetermined color, a manually operative setting device, and means, rendered effective on operation of said device, to counteract the effect of said carriage-controlled setting means, so as to prepare said machine to effect a computation of a different character and to print in a different color in said zone.

2. In a computingmachine, in combination, a variably settable computing mechanism, capable of efiecting computations in either addition or subtraction, dependent upon its setting, means for printing numbers computed in either of two different colors, said rinting means including variably settable bichrome mechanism for selectively determining the printing color at each printing operation, said printing means also including a traveling carriage and means controlled thereby for determining a zone in which a number printed may be computed, means, including parts normally operated on movement of said carriage into said zone, for effecting an automatic setting, by varying the relations of parts of said mechanisms, so as to prepare said machine to effeet a computation in subtraction and to print in a predetermined one ofsaid colors, a manually operative setting device, and means, rendered effective on operation of said device, to counteract the effect of said carriage-controlled setting means, so as to prepare said machine to effect a computation in addition and to print in the other of said colors in said zone.

3. In a computing machine, in combination, a variably settable computing mechanism, capable of effecting computations of panacea different character, means for printing num- I one of said zones, for efiecting an automaticv setting, by varying the relations between parts of said mechanisms, so as to prepare said machine to effect a computation of a predetermined character, and to print in a predetermined color, said setting means also including parts normally operated on movement of said carriage into a diflerent zone, for effecting a second automatic setting, by a different variation of the relations between parts of said mechanisms, so as to prepare said machine to effect. a computation of the same character and to print in a different color, a manually operative setting device, and means, rendered effective on operation of said device, to counteract the effect of said carriage-controlled setting means for the second-mentioned zone, so as to prepare said machine to effect a computation of a different character and to print in said first-mentioned color when said carriage is in said second-mentioned zone.

4:. In a computing machine, in combination, a variably settable computing mechanism, capable of effecting computations in either addition or subtraction, means for printing numbers computed in either of two distinguishing colors, said printing l means including variably settable bichrome mechanism for selectively determining the printing color at each printing operation, said printing means also including a traveling carriage and means controlled thereby for determining zones in which numbers printed may be computed, means, including parts operated on movement of said carriage into one of said zones, for efiecting an automatic setting, by varying the relations between parts of said mechanisms, so as to prepare said machine to effect a computation in subtraction and to print in a predetermined one of said colors, said setting means also including parts normally operated on movement of said carriage into a different zone, for effecting a second automatic setting, by a different variation of relation between parts of said mechanisms, so as to prepare said machine to effect a computation in subtraction and to print in the other of said colors, a manually operative setting device, and means, rendered effective on operation of said device, to counteract the effect of said carriage-controlled setting means for the second-mentioned zone, so as to prepare said machine to effect a computation in addition and to print in said firstmentioned color when said carriage is in said second-mentioned zone.

5. 111 a computing machine, in combination, a variably settable computing mechanism. capable of efiecting computations of different character, means for printing numbers computed in any one of a plurality of different colors, said printing means including variably settable polychrome mechanism for selectively determining the printing color at each printing operation, said printing means also including a traveling carriage and means controlled thereby for determining zones in which numbers printed may be computed, means, normally effective on movement of said carriage into one of said zones, to prepare said machine to effect a computation of one character and to print in one of said colors, means, including parts normally operated on movement of said carriage into another of said zones, for automatically effecting a setting, by varying the relations of parts of said mechanisms, so as to prepare said machine to effect a computation of different character and to print in the same color. a manually operative setting device, and means, rendered effective on operation of said device, to effect a setting different from said carriage-determined setting for one of said zones, so as to prepare said machine to effect. a computation of a different character and to print in a different color from the character and color which would be determined bysaid carriage-controlled setting, when said carriage is in said zone.

6. ln a computing machine, in combination, a variably settable computing mechanism, capable of effecting computations in either addition or subtraction. means for printing numbers computed in either of two different colors. said printing means including variably settable bichrome mechanism for selectively determining the color at each printing operation. said printing means also including a traveling carriage and means controlled thereby for determining zones in which numbers printed may be computed. means. normally effective on movement of said carriage into one of said zones, to prepare said machine to effect a computation in addition, and to print in one of said colors. means. including parts normally operated on movement of said carriage into another of said zones. for automatically effecting a setting by varying the relations of parts of said mechanisms so as to prepare said machine to effect a computation in subtraction, and to print in the same color, a manually operative setting device, means rendered effective on operation of said device to counteract said carriage-determined setting for one of said zones, a second manually operative setting device, and means rendered effective on operation thereof to counteract said carriage-determined setting for the other of said zones, said manually operative setting devices and the means controlled thereby thus constituting means to prepare the machine for effecting a computation of opposite character and to print in the alternate color, when said carriage is in either of said zones.

7 In a computing machine, in combination, a variably settable computing mechanism normally set in readiness to effect a computation in addition, means normally tending to set said mechanism in readiness to effect a computation in subtraction, restraining means therefor, operating mechanism for said computing mechanism including a motive device for driving the same, means, including a traveling carriage, for determining a computing zone, means, including parts operated on movement of said carriage into said zone, for rendering said restraining means ineffective so as to release said setting means and permit the same to effect a subtraction setting, means actuated by said operating mechanism when said motive device is rendered effective for restoring said subtraction-setting means, if set, and manually operative means, effective, if operated, to render said motive device effective to actuate said operating mechanism and to retain a restored setting of said subtraction-setting means while said carriage is in said zone.

8. In a computing machine, in combination, a variably settable computing mechanism. normally set in readiness to effect a computation in addition, operating means for said computing mechanism including a motive device for driving the same, means, including a traveling carriage, for determining a computing zone, means, including parts normally operated on movement of said carriage into said zone, for effecting a setting of said computing mechanism in readiness to effect a computation in subtraction, means actuated by said operating means when said motive device is rendered effective for restoring the normal setting of said computing mechanism, if set for subtraction. and manually operative means. effective, if operated before said carriage leaves said zone, to render said motive de vice effective to actuate said operating means, and to maintain a normal setting of said computing mechanism while said carriage is in said zone.

9. The combination with computing mechanism and a general operator therefor, of a subtraction bar, a spring tending to automatically actuate said bar, a traveling carriage, a detent for said subtraction bar releasable by said carriage just as the latter enters a subtraction zone, to permit the actuation of said subtraction bar by said spring, a drive for said general operator acting during its initial movement, to restore said subtraction bar to normal position, and manually operable means adapted to set into action said general operator drive and to hold said subtraction bar in normal position when the carriage is in said subtraction zone.

10. The combination with a computing mechanism and a general operator therefor, of subtraction-setting mechanism, means tending to automatically actuate said setting mechanism, a traveling carriage, a detent for'said setting mechanism releasable by said carriage, just as the latter enters a computing zone, to permit the actuation of said setting mechanism by said automatic means, a drive for said general operator automatically set into action just as the carriage leaves said computing zone, and manually operable means adapted to set into action said general operator drive to restore said subtraction-setting mechanism before said carriage leaves said zone, said manually operable means including means for maintaining the restored setting While said carriage is in said zone.

11. In a computing machine, in combina tion, a variably settable computing mechanism normally set in readiness to effect a computation in addition, operating means for said computing mechanism including a motive device for driving the same, means including a traveling carriage for determining a computing zone, means including parts operated on movement of said carriage into said zone for eifecting a setting of said computing mechanism in readiness to effect a computation in subtraction, means actuated by said operating means when said motive device is rendered effective for restoring the original setting of said comput ing mechanism, means including parts operated on movement of said carriage out of said zone for rendering said motive device effective to cause an actuation of said operating means, and manually operative means effective, if operated before said carriage leaves said zone, to render said motive device effective to actuate said operating means, and to maintain a restored original setting of said computing mechanism While said carriage is in said zone.

12. The combination with a computing mechanism and a general operator therefor, of a setting mechanism for determining the character of the arithmetical operation, means tending to automatically actuate said setting mechanism, a traveling carriage, means controlled thereby to determine a computing zone, a detent for said setting mechanism releasable by said carriage just as the latter enters the computing zone to permit the actuation of said setting mechanism by said automatic means, a drive for said general operator acting during its initial movement to restore said setting mechanism to normal position, manually operable means adapted to set into action said general operator drive and to hold said setting mechanism in normal position when the carriage is in said zone, and means to release said holding mechanism when the carriage leaves said zone.

13. In a computing machine, in combination, a variably settable computing mechanism normally set in readiness to effect a computation in addition, operating means for said computing mechanism including a motive device for driving the same, means including a traveling carriage for determining a computing zone, means including parts operated on movement of said carriage into said zone for effecting a setting of said computing mechanism in readiness to effect a computation in subtraction, means actuated by said operating means when said motive device is rendered effective for re storing the original setting of said computing mechanism, manually operative means effective, if operated before said carriage leaves said zone, to render said motive device effective to actuate said operating means and to maintain a restored original setting of said computing mechanism while said carriage is in said zone, and means, including parts operated on movement of said carriage out of said zone, for restoring said manually operative means to normal condition.

14. The combination with a computing mechanism and a general operator therefor,

of state-setting mechanism, means tending v to automatically actuate said setting mechanism, a traveling carriage, means controlled thereby for determining a computing zone, a detent for said setting mechanism normally releasable by said carriage just as the latter enters a computing zone to permit the actuation of said setting mechanism by said automatic means, a drive for said general operator acting during its initial movement to restore said setting mechanism to normal position, and a manually operable device effective, if operated either before or after said carriage enters said zone, to set into action said general operator drive and to hold said setting mechanism in normal posi tion while said carriage is in said zone.

15. The combination with a computing mechanism, and a general'operator therefor, of a subtraction bar, a spring tending to automatically actuate said subtraction bar, a traveling carriage, a detent for said subtraction bar releasable by said carriage just as the latter enters a subtraction zone to permit the actuation thereof by said spring, a drive for said general operator acting during its initial movement to restore said sub- 

